F51.9 ICD-10-CM Code: Sleep disorder not due to a substance or known physiological condition, unspecified

F51.9 is the ICD-10-CM diagnosis code for sleep disorder not due to a substance or known physiological condition, unspecified. This code describes a sleep problem that cannot be attributed to drug use, alcohol, or a known medical condition. It is used when the specific type of sleep disorder is not documented or cannot be determined. F51.9 sits in the ICD-10-CM chapter for mental, behavioral and neurodevelopmental disorders (f01-f99), within the section covering behavioral syndromes associated with physiological disturbances and physical factors (f50-f59).

F51.9 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

Use this code only when the sleep disorder is primary (not caused by substances, medications, or other medical conditions) and the specific type cannot be identified.